Cook is outspoken on rights issues. Back in 2014, he publicly announced he was gay in an article for Businessweek, writing: "Being gay has given me a deeper understanding of what it means to be in the minority and provided a window into the challenges that people in other minority groups deal with every day ... I don't consider myself an activist, but I realize how much I've benefited from the sacrifice of others. So if hearing that the CEO of Apple is gay can help someone struggling to come to terms with who he or she is, or bring comfort to anyone who feels alone, or inspire people to insist on their equality, then it's worth the trade-off with my own privacy."

Back in December 2015, the Alabama native was awarded the "Ripple of Hope Award" by the Robert F. Kennedy Center for Justice & Human Rights, speaking out in defence of LGBT people and refugees when he accepted it.

"Today, more than half of the states in this country still don't offer basic protections to gay or transgender people, leaving millions of people vulnerable to being fired or evicted because of who they are or who they love," he said, according to Bloomberg. "Today, some in our country would turn away innocent men, women and children seeking refuge ... regardless of how many background checks they may submit to, simply based on where they were born. Victims of war and now victims of fear and misunderstanding."

Now, he's joining the organisation's board.

In a statement accompanying the news, Cook said: "Growing up, I was inspired by Robert Kennedy's infinite hope for humanity and his belief that people at their core are good, sharing universal goals for themselves and the world in which we live ... Robert Kennedy spoke to our highest aspirations, calling Americans from all walks of life to fight for something better. He was and is a hero and role model to me, and I am honored to serve alongside Kerry and the rest of the board to advance his message of justice and equality."